That's kind of a odd choice. If you're just looking for games, get the 360. But if you're going to need the laptop for other things (websurfing. etc) then maybe you should get a laptop. Just keep in mind a decent gaming laptop will run you more and have less options for customization than a regular computer.

A lot of 360 games can be played in a PC (Street Fighter IV, Resident Evil 5, Elders Scrolls IV, Fallout 3, Portal, BioShock, Braid, Mass Effect...), even with a Xbox controller and a lot of them without a high requisites. If you have another console (I expect a Nintendo one), and need a laptop for other things like work, buy with no doubt a laptop.

If you're main concern is games, go for the 360 (probably cheaper than a decent gaming PC anyways). Also, Microsoft is bringing Internet Explorer to 360 this fall (and it already has a free YouTube app).

What games are on the 360 that you like? Are they exclusives or multiplats? Is local multiplayer important to you? If its purely for gaming then a 360 would be the more affordable choice. Do you need a laptop to take to school or something because otherwise a desktop would be the better choice.They're more affordable compared to laptops with similar specs and you can upgrade them rather than get a whole new one, if all you want are games like Fallout, Mass Effect, or The Elderscrolls that are on both you can have the best of both worlds

Well remember that most laptops (except for dedicated gaming ones) aren't that great to run games on.
I have a macbook, for example, and it sometimes struggles to even play a relatively small game like Bastion!

I'd suggest a PC, if not for other things than gaming, then for specific genres that are simply meant to be played with a mouse and keyboard, most prominently FPS' and RTS'. You can also choose from a wide variety of emulators and from lots and lots of indie games. Games are cheaper due to frequent sales and devs get a better cut, because they don't have to pay 30+% to console manufacturers. And as a nice bonus, you can try developing your own game, too

Depends on how much your willing to shell out since decent dedicated gaming laptops/desktops over here go for around the £1000 mark. So if you want it for just gaming you should just go with a 360 since you can find Elite's for around £100-£200. But if you want something primarily for multitasking and internet browsing then maybe a laptop would be your better choice.

Ultimately it depends on how much you want to spend and what you want it for.

If you already have a PS3, 100% go for the laptop, it is much more practical in the long run.

If you don't have a PS3, I would still say to go for the laptop as long as it has high enough specs for WoW and Sims, but most laptops these days can run them anyway. Just check the required specs for the games you want before you buy.